为提高链霉菌菌株LG-9发酵液的抑菌活性,在单因素试验的基础上,利用Minitab软件中的Plackett-Burman设计和响应面分析,以发酵液对棉花黄萎病菌(Verticillium dahliae)的抑菌圈大小为响应值,对链霉菌LG-9的液体发酵条件进行优化。结果表明,菌株LG-9的最佳发酵条件为250 m L三角瓶装样量101.19 m L、培养基初始p H 7.2、接种量7.5%、温度31.32℃、转速160 r/min和摇培时间69.02 h。在此条件下的抑菌圈直径大小为22.45 mm,较未优化前提高10.43%。
[Objective]The paper was to study the relationship between temperature and development of Potosia brevitarsis Lewis.[Methods]Six constant temperatures(21,24,27,30,33 and 36℃)were set in the laboratory to study developmental threshold temperature and effective accumulated temperature of P.brevitarsis.[Result]The developmental durations of various states of P.brevitarsis were shortened with the increasing temperature ranged from 21℃to 36℃;the developmental rates were accelerated with the increasing temperature.The developmental threshold temperatures of egg,larva,pupa and pre-oviposition of adult were estimated to be 12.79,9.15,14.86 and 13.80℃,respectively;the effective accumulated temperature were 136.25,3 031.31,308.92 and 98.35 d·℃,respectively.The developmental threshold temperature and effective accumulated temperature for one complete generation were 9.96℃and 3 628.73 d·℃,respectively.Combined with meteorological data,the theoretical generation number of P.brevitarsis occurred in Shihezi was presumed to be one per year,which was basically coincided with actual occurrence generations in fields.[Conclusion]The paper provided theoretical basis for effective control against P.brevitarsis.
Liu ZhengSun YanChen BingZhang XuekunWang ShaoshanLi Guoying